1. Field of the Invention
This invention relates to a polymer composition or concentrate. More particularly, it relates to polymer composition or concentrate which is useful as a lubricating oil additive.
2. Description of the Background
As a lubricating additive a concentrated polymer emulsion comprising: (1) a dispersed phase of an olefinic copolymer, (2) a dispersing phase of a polymer predominantly comprising a (meth)acrylate ester monomer, (3) a vehicle which is a good solvent for the esters in said dispersing phase and a substantially poorer solvent for the olefinic copolymer by virtue of the esters dissolved in said vehicle, and (4) a graft or block copolymer formed from olefinic monomers and (meth)acrylate ester monomers has been proposed in U.S. Pat. No. 4,290,925. Such concentrated polymer emulsions do not exhibit sufficiently satisfactory performance properties. The viscosity of these emulsions is not sufficiently reduced, and the emulsions also show, because they are emulsions, thixotropic properties, which are undesirable for the handling of the products.